Portsmouth owner Balram Chainari admits none of the four interested parties have proof they can fund a takeover of the club.
Chainrai's spokesman Phil Hall said none of the four consortiums had made a credible offer.
Hall said: "Mr Chainrai is looking for absolute credible proof of funds and trying to avoid the mistakes the previous regimes have made.
"Administration would mean the club re-emerging as a healthy financial entity and it would then become an attractive proposition for a potential buyer who could invest new funds in re-building the club's future.
"The serving of this notice means the winding up order is automatically suspended. It means the club is safe, it can fulfil its fixtures and as far as is possible it is business as usual.
"Mr Chainrai has agreed to continue funding the club going forward until its long-term future is decided and he will also pay for the administration process out of his own pocket."